1) Field of the Invention:
The present invention relates to coating compositions, and more specifically to water- and/or moisture-curing coating compositions capable of forming films excellent in surface properties. Particularly, this invention relates to fluoropolymer-base coating compositions.
2) Description of the Related Art:
Coating compositions have conventionally been used widely to form a film on the surfaces of various structures, buildings, articles and the like so as to prevent corrosion and deterioration of such coated items and in addition, to provide them with excellent external appearance and surface functions.
Various coating compositions have been known as such protective and decorative ones. In recent years, fluoropolymer-base coating compositions have been increasingly finding wide-spread utility as coating compositions excellent in various durabilities such as weather resistance and antifouling property.
Fluoropolymers inherently have excellent weather resistance, heat resistance, water repellency, chemical resistance, electrical properties, etc. They, however, are not soluble in general paint solvents. Accordingly, they have been used exclusively for extremely special applications.
In order to overcome these drawbacks, fluoropolymers soluble in general paint solvents have been developed each by copolymerizing a fluorine-containing monomer with a general fluorine-free monomer. Such copolymerizable resins, however, contain fluorine-free monomer moieties, thereby unavoidably reducing inherent excellent essential properties of fluoropolymers such as antifouling property, abrasion resistance, non-tacky property and lubricating property.
In addition, the above fluoropolymers can be provided with various high durabilities when they are used as a two-pack type paint with a curing agent, because they contain functional groups, which have various reactivities, introduced therein. Most of the curing agents employed now, however, are melamines or isocyanates, which require a heating unit upon curing under heating. Such curing agents are accompanied by the danger of fires and also a problem of inferior curing. They also involve a problem of pot life even in the case of cold setting.